Bhopal, India (CNN) -- T.R. Chouhan walked solemnly through the rusted remains of the Union Carbide pesticide factory in Bhopal, India. "I come here frequently," he said. "We used to work here, and now this is the condition of the plant. So it feels really bad."

Chouhan was a 10-year veteran employee of the plant when disaster struck 25 years ago. Shortly after midnight on December 3, 1984, a cloud of methyl isocyanate gas wafted into the Bhopal atmosphere. Outside the factory's concrete walls, quiet neighborhoods quickly became chaotic.

"Everybody started screaming, 'There's a gas leak, there's a gas leak!' So we started running," recalled Bhopal resident Bashiran Bi.

"When we stepped out of the house, there was no room on the streets," remembered Hamid Qureshi, another survivor. "There was chaos everywhere. People were running in each and every direction."

Within hours, more than 3,000 people were dead. Thousands more died in the coming days, months and years.

"And people still continue to die," said Satinath Sarangi, managing trustee of the Sambhavna Trust Clinic. "This month, this week, someone would have died an untimely death because of the exposure back in 1984. And there are still 100,000 or more people suffering from chronic illnesses."

Sarangi's clinic is a charitable trust in Bhopal that provides free medical care and treatment to survivors. More than 150 patients show up every day; in all, more than 22,000 people are registered for long-term care. Sarangi came to Bhopal immediately after the disaster, thinking he would help out for a week or so. He has been there ever since.

Similarly, Abdul Jabbar led his first public demonstration on behalf of gas victims shortly after the disaster. And he has been holding them ever since.

Jabbar is the head of the Bhopal Gas-Affected Working Womens' Union, whose members meet in a public park every Saturday, railing against injustices to anyone who will listen.

"We have held more than 5,000 protests here," Jabbar said. "We protest against the state, and whoever necessary."

Jabbar's core demands echo those of other activists. They want more medical and financial assistance, they want someone to clean up the dilapidated Union Carbide site, and they want someone to be held criminally responsible for the disaster.

The U.S.-based Union Carbide Corporation paid a $470 million settlement in 1989, after which it denied any further liability or responsibility for cleaning up the site. In a written statement to CNN, Union Carbide spokesman Tomm Sprick said, "Our understanding is that the (Indian) Central and State governments have plans for site clean up and we're hopeful they will follow through with their remediation plans."

Sixteen years after the disaster, Union Carbide became part of the Dow Chemical Corporation. Dow also rejects demands that it clean up the Bhopal site. "The fact is that Dow never owned or operated the facility in Bhopal," wrote Dow spokesman Scot Wheeler, in a statement to CNN.

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Union Carbide and many local government officials insist that there is no conclusive evidence of any groundwater contamination.

Chouhan disagreed. "The smell from the water that comes out of the local hand pumps is the same that you can smell standing here right now."

Chouhan, like Sarangi and Jabbar, said he was committed to making sure the disaster was never forgotten.

"If we don't learn from it," he warned, "tomorrow, another Bhopal will happen."

"With the passage of time, we try to forget a lot of things," Jabbar added. "Unfortunately, what happened in 1984, neither Bhopal nor the country learned anything from it."

Most people think the disaster was "a horrible thing," Sarangi said, "but it happened in the past, and they were paid a lot of money, and now everything's okay. So the first news we have to break, which is sad news: It's ongoing."